Sexual dysfunction in humans and animals involves a multitude of physiological and/or psychological factors. Sexual dysfunction in male humans and animals involves lack of penile erection and sexual desire. Sexual dysfunction in female humans and animals involves lack of sexual desire and lack of vaginal lubrication, sensitivity, and engorgement. To engage in satisfying sexual intercourse both partners must be stimulated both psychologically and physically, their sex organs must function and they must have sufficient sexual desire.
In male humans and animals sufficient sexual desire and penile erection are necessary for proper sexual function. There are a variety of pharmacological and surgical options for those suffering from erectile dysfunction however, each option is not without its risks. Available pharmacological options for human males include sildenafil and alprostadil while surgical options include flexible and inflatable penile implants. However, there is a lack of treatment options proven to increase the level of sexual desire.
For male animals, particularly race horses and endangered species, there is a great need for a pharmacologic option to improve breeding. Current optuion include yohimbine and hormone therapy, both of which offer only limited success.
In female humans and animals sufficient sexual desire and sufficient vaginal lubrication, sensitivity, and engorgement are necessary for proper sexual function. For female humans, various options are available for vaginal dryness that include hormone replacement therapy and vaginal lubricants among others. Unfortunately there are many adverse reactions associated with the pharmacological treatments and the vaginal lubricants do not treat the underlying cause of vaginal dryness. In addition none of these choices offers a risk free choice which also increases the level of sexual desire. Infertility in humans and animals is treated pharmacologically or surgically and each choice is associated with significant risk.